Agilent Technologies G6691A User manual

Agilent Technologies
Agilent G6691A
ADM Flow Meter
Operating
Instructions

Notices
© Agilent Technologies, Inc. 2016
No part of this manual may be reproduced in any form or
by any means (including electronic storage and retrieval
or translation into a foreign language) without prior
agreement and written consent from Agilent Technolo-
gies, Inc. as governed by United States and international
copyright laws.
Manual Part Number
G6691-90000
Edition
First edition, October 2016
Printed in USA
Agilent Technologies, Inc.
2850 Centerville Road
Wilmington, DE 19808-1610 USA
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The material contained in this document is provided “as
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future editions. Further, to the maximum extent
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The hardware and/or software described in this docu-
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Safety Notices
CAUTION
CAUTION
A CAUTION notice denotes a hazard. It calls
attention to an operating procedure, practice,
or the like that, if not correctly performed or
adhered to, could result in damage to the
product or loss of important data. Do not pro-
ceed beyond a CAUTION notice until the indi-
cated conditions are fully understood and
met.
WARNING
A WARNING notice denotes a hazard. It
calls attention to an operating procedure,
practice, or the like that, if not correctly
performed or adhered to, could result in
personal injury or death. Do not proceed
beyond a WARNING notice until the
indicated conditions are fully understood
and met.
2

3
Agilent Technologies
Introduction 4
Principles of Operation 6
Display 7
Using the Flow Meter Stand 8
Power/Mode Button 9
Select Button 9
Switching the ADM Flow Meter On and Off 9
Operating Modes 10
Making a Flow Measurement 12
Storing Flow Measurements 13
Reading and Setting a Split Ratio 15
About Flow Measurements 16
Info Mode 17
USB Interface 21
Warning and Error Indications 23
Replacing the Cartridge 24
Replacing Batteries 27
Upgrading the Firmware/Retrieving Certificate of
Calibration 30
A Note About Back Pressure 30
Technical Support 30
Product Specifications 31

4 Agilent ADM Flow Meter Operating Instructions
Introduction
Congratulations on your purchase of the new Agilent ADM Flow Meter! The ADM
Flow Meter has been designed to accurately measure the flow of gases commonly
used in Gas Chromatography without knowledge of the gas type or mixture compo-
sition. A complete ADM Flow Meter consists of a Flow Meter Mainframe and a
Flow Meter Cartridge. The Flow Meter Mainframe contains the display, keypad,
batteries, and microprocessor; while the Flow Meter Cartridge contains all of the
hardware used to make a flow measurement. Flow Meter Cartridges are individu-
ally factory calibrated and can easily be replaced with a new cartridge without
returning the Flow Meter to Agilent. This eliminates the hassle and downtime
associated with maintaining the calibration of an instrument that would normally
need to be sent to an outside facility for calibration on a yearly basis.

Agilent ADM Flow Meter Operating Instructions 5
Included in the packaging are the following items:
Table 1 Packing List
1 ADM Flow Meter Mainframe
1 ADM Flow Meter Cartridge
1 USB Cable
1 Screwdriver, Phillips head
3 AA Alkaline Batteries
1 Calibration Certificate
1 Declaration of Conformance
1 Quick Start Guide

6 Agilent ADM Flow Meter Operating Instructions
Principles of Operation
The ADM Flow Meter provides continuous, real time measurements of dry gas
flows, such as those used for Gas Chromatography. Unlike bubble flow meters, the
ADM Flow Meter operates without liquids, bubbles, or glass parts. When acti-
vated, a solenoid actuated valve interrupts the gas flow momentarily. The gas flow
moves a diaphragm in proportion to the flow rate. This movement is transformed by
the Flow Meter's electronics into a digital value which is displayed on the Flow
Meter's screen. The ADM Flow Meter provides two different types of flow mea-
surements: volumetric flow (mL/min) and mass flow reported in standard cubic
centimeters per minute (sccm). Mass flow values are calculated from the volumet-
ric measurements by correcting for ambient temperature and atmospheric pres-
sure, and reporting the flow rate referenced to 0 °C and 1 atmosphere of pressure,
using digital temperature and pressure sensors installed in the mainframe of the
flow meter.
The ADM Flow Meter employs a replaceable cartridge that contains all parts sub-
ject to calibration. This eliminates the need to ship the entire meter back to the fac-
tory to maintain its calibration. The cartridge calibration is valid for a period of one
year from its first use. A new, calibrated cartridge can be ordered in advance, and
then installed when necessary.
When the flow meter is powered on with a new cartridge installed, the current date
is written to the cartridge’s memory based on the mainframe’s internal clock. Each
time the flow meter is turned on, the meter will compare the current date to the ini-
tial turn on date of the cartridge. If the initial turn on date is more than a year from
the current date, the flow meter will flash a notification to the user that the calibra-
tion has expired. The flow meter will still function with an expired calibration. This
eliminates downtime, enabling you to keep working. See “Replacing the
Cartridge" on page 24.
CAUTION The measurement calibration can be affected if the instrument
is exposed to temperatures above 50 °C for extended periods
of time.
Please inspect the temperature label attached to the inside of
cartridge packaging to verify that your cartridge has not been
damaged in shipment. A grey circle is acceptable, a black circle
indicates that the cartridge may have been exposed to an
extreme temperature.
Please contact Agilent Technical Support if your cartridge is
delivered with a temperature indicator that is black.

Agilent ADM Flow Meter Operating Instructions 7
The ADM Flow Meter is powered by three AA alkaline batteries. Power can also be
supplied via the micro USB port located on the side of the unit.
Display
The ADM Flow Meter has a bright OLED display with a battery strength indicator.
The unit automatically adjusts the resolution of the display in response to various
gas flow ranges as follows:
When the battery strength indicator shows that the battery strength is low, replace
the batteries. See “Replacing Batteries" on page 27.
NOTE Using the USB port to supply power does not recharge the
installed batteries.
NOTE The ADM Flow Meter can also be powered by rechargeable batter-
ies, but the battery indicator may not display correctly.
Flow (mL/min)
Display resolution
(mL/min)
0 - 9.99 0.01
10.0 - 99.9 0.1
100 - 750 1.0

8 Agilent ADM Flow Meter Operating Instructions
Using the Flow Meter Stand
The flip down wire stand will give you a better viewing angle when the ADM Flow
Meter is placed above bench level. Pull the stand down until it is in the locked posi-
tion.
Stand

Agilent ADM Flow Meter Operating Instructions 9
Power/Mode Button
The Power/Mode button is used to switch the ADM Flow Meter on and off, as well
as to scroll through and select the different operational modes.
•To turn on the instrument briefly press and release the Power/Mode button.
•To turn off the instrument press and hold the Power/Mode button for three sec-
onds.
•To scroll through the available modes, when the instrument is on, briefly press
and release the Power/Mode button.
Select Button
The Select button is used to access additional functionality within the operating
modes. This includes storing flow measurements, setting a reference value for the
Split Mode, and changing the settings.
Switching the ADM Flow Meter On and Off
With the ADM Flow Meter powered off, briefly press and release the Power/Mode
button to turn the unit on. The display will flash the Agilent logo for approximately
3 seconds, and then begin operating. During startup, the microprocessor will run a
self-diagnostic test to ensure the unit is functioning properly.
With the unit powered on, press and hold the Power/Mode button for three sec-
onds to power down the unit.

10 Agilent ADM Flow Meter Operating Instructions
Operating Modes
With the ADM Flow Meter switched on, briefly press the Power/Mode button to
scroll through the different operational modes.
The available modes are as follows:
Volumetric flow mode
This is the default mode on power up. In this mode, the volumetric flow rate is dis-
played in mL/min.
Mass flow mode
In this mode, the volumetric flow rate is corrected taking into account the current
atmospheric pressure and ambient temperature. The flow rate is displayed in sccm
(standard cubic centimeters per minute) referenced to 1 atmosphere of pressure
and 0 °C.
Split mode
In this mode, you can store a flow measurement as a reference value, and then
compare subsequent flow measurement values as a ratio of the current measure-
ment to the reference measurement. This is useful when trouble shooting a GC
Inlet.

Agilent ADM Flow Meter Operating Instructions 11
Info mode
Info mode provides details on the flow meter and the currently installed cartridge,
including the calibration expiration date. In addition, Info Mode allows you to set
the display brightness and control the Auto off functionality.

12 Agilent ADM Flow Meter Operating Instructions
Making a Flow Measurement
1When the unit is powered on, it defaults to volumetric flow mode. (If you want to
use the mass flow mode, briefly press the Power/Mode button.)
2Connect the flexible tubing to the gas source to be measured.
3Wait for the reading to stabilize (1 - 2 seconds) and then observe the reading.
CAUTION Make sure that the flow to be measured is within the range of
the flow meter. Over ranging the flow meter can damage the
transducer.
NOTE Always turn the flow meter on before connecting it to a flow
source.
NOTE Low flows (less than 1 mL/min) may take up to 5 seconds for the
reading to stabilize

Agilent ADM Flow Meter Operating Instructions 13
Storing Flow Measurements
When in the volumetric flow mode or mass flow mode up to four flow values can
be stored on the screen for reference later.
To store one or more values:
1With either volumetric flow mode or mass flow mode displayed, briefly press the
Select button. The measurement storage screen appears. Any previously stored
values are displayed on the screen. If the cartridge is unused, the values will be
listed as nan (not a number).
2Press and hold the Select button to clear the previously stored values.
3Press the Select button to store a value to the first available slot.
4Repeat step 2 to store additional values to the subsequent slots. Up to four val-
ues can be stored.

14 Agilent ADM Flow Meter Operating Instructions
To clear the stored values:
•Hold down the Select button. All of the stored values are cleared from memory.

Agilent ADM Flow Meter Operating Instructions 15
Reading and Setting a Split Ratio
In split mode, you can store a flow measurement as a reference value, and then
compare subsequent flow measurement values as a ratio of the current measure-
ment to the reference measurement. This is useful when verifying or troubleshoot-
ing the operation of a Gas Chromatograph Inlet.
To read and set a split ratio:
1With the unit switched on, repeatedly press the Power/Mode button until Split
mode is displayed.

2Turn off the detector gases.
3Connect the flexible tubing to the GC column gas flow.
4Wait for the reading to stabilize (1 - 2 seconds).
5Briefly press the Select button. The current reading is stored as the reference
value. The ratio value is displayed as 1:1.
6Disconnect the flexible tubing from the GC column flow and then connect it to
the split vent, or the gas flow that you want to compare. The display shows the
ratio directly.
7Adjust for the desired ratio by adjusting the flow of the split vent, or the other
reference flow, until the required ratio is displayed.
To clear the stored reference value, press the Select button.
NOTE Accurate column flow rates can only be determined when detec-
tor gases have been turned off.

16 Agilent ADM Flow Meter Operating Instructions
About Flow Measurements
When compared with readings from the ADM Flow Meter, measurements taken
with bubble-type flow meters may show a difference. This does not indicate a prob-
lem with your ADM Flow Meter. As a consequence of the ideal gas law, measure-
ments made with both soap bubble meters and the ADM Flow Meter are
temperature sensitive. However, bubble-type flow meters add water vapor to the
gas being measured, which introduces error into the flow rate measurement.
Even when accurately calibrated, soap bubble meters typically read slightly higher
than the ADM Flow Meter. The higher readings arise from relatively high concen-
trations of water vapor present in the soap bubble apparatus. At room temperature,
water vapor can raise readings by nearly 4%. This unfortunate property is amplified
by the effect of temperature. As the measured gas or the flow meter itself is
warmed, the amount of water vapor increases, and the readings can be much
higher than the true flow rate.

Agilent ADM Flow Meter Operating Instructions 17
Info Mode
Info mode provides details on the flow meter and the installed cartridge. In addi-
tion, Info Mode allows you to set the display brightness and control the Auto off
functionality.
To access Info mode:
•With the unit switched on, repeatedly press the Power/Mode button until Info
mode is displayed.
Once in Info mode, pressing the Select button scrolls through the available Info
mode screens.
Cartridge and flow meter information
To view cartridge and flow meter details:
•With Info mode displayed, press the Select button to cycle through the available
screens.
The first screen displays information about the currently installed cartridge. This
includes the date that the cartridge was first used, and the date that the
cartridge is due to be replaced. In addition, a graphic representation of the
remaining life of the installed cartridge is displayed. (See “Replacing the
Cartridge" on page 24 for details on replacing a cartridge.)
The second screen displays the cartridge serial number (SN) and Key number.
The Key number is used to access the online copy of the cartridge's calibration
certificate. (See “Upgrading the Firmware/Retrieving Certificate of
Calibration" on page 30 for details on retrieving a digital copy of the Certificate
of Calibration for your cartridge.)

18 Agilent ADM Flow Meter Operating Instructions
The third screen displays the flow meter model number (MDL), serial number
(SN) and firmware version number (Ver). (See “Upgrading the
Firmware/Retrieving Certificate of Calibration" on page 30 for details on
upgrading the flow meter firmware.)
Display brightness
Display brightness can be set to high or low.
To change the display brightness setting:
1With Info mode displayed, press the Select button to cycle through the available
screens until the Brightness screen is displayed.
2Briefly press the Power/Mode button to change the selected value. The screen
brightness changes based on the selected value.
3Press the Select button to cycle through the available screens until you are
returned to the Info mode screen with the cartridge statistics displayed.
Auto off
When the unit is turned on, the unit defaults to Auto off. This means that every
time the unit is activated, a “power-off” cycle begins, lasting 10 minutes.
To disable this feature:
1With Info mode displayed, press the Select button to cycle through the available
screens until the Auto off function is displayed.
2Briefly press the Power/Mode button to toggle the Auto off function On and Off.
3With the desired setting highlighted, briefly press the Select button.
The flow meter will now operate continuously until it is manually turned off.

Agilent ADM Flow Meter Operating Instructions 19
4Press the Select button to cycle through the available screens until you are
returned to the Info mode screen with the cartridge statistics displayed.
Errors/Warnings
With Info mode displayed, press the Select button to cycle through the available
screens until the Error/Warning screen is displayed.
Error number definitions are as follows:
Error
number Type Description Troubleshooting
0001 Error No calibration informa-
tion.
Contact Agilent Technical
Support.
0002 Error Flow meter is not verified. Contact Agilent Technical
Support.
0003 Error Pressure/temperature
sensor failure.
Contact Agilent Technical
Support.
0004 Error No cartridge detected. Install a valid cartridge.
0005 Warning No ADM information. Contact Agilent Technical
Support.
0006 Warning Auto-recovery mode. Shut down and restart the
ADM Flow Meter.

20 Agilent ADM Flow Meter Operating Instructions
For information on contacting Agilent Technical Support, see “Technical
Support" on page 30.
0007 Warning Measurement exceeds
instrument range.
Measure gas flows within
the acceptable flow range.
0008 Warning Cartridge calibration
expired.
Install a new cartridge.
0009 Warning RTC (real time clock)
backup battery low.
Contact Agilent Technical
Support.
0010 Warning Out of operating tempera-
ture range condition (0 -
45 C
Operate the flow meter
within the acceptable tem-
perature range.
0011 Warning Out of operating atmo-
spheric pressure range.
Operate the flow meter
within the acceptable atmo-
spheric pressure range.
Error
number Type Description Troubleshooting